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Related papers: Shear viscosity of a hadronic gas mixture

200 papers

We investigate the shear viscosity of a pion gas in relativistic kinetic theory, using the Nambu-Jona-Lasinio model to construct the pion mass and the pi-pi interaction at finite temperature. Whereas at low temperatures the scattering…

High Energy Physics - Phenomenology · Physics 2012-11-07 Klaus Heckmann , Michael Buballa , Jochen Wambach

We estimate the shear and the bulk viscous coefficients for a hot hadronic gas mixture constituting of pions and nucleons. The viscosities are evaluated in the relativistic kinetic theory approach by solving the transport equation in the…

Nuclear Theory · Physics 2017-03-13 Utsab Gangopadhyaya , Snigdha Ghosh , Sukanya Mitra , Sourav Sarkar

We compute the shear viscosity, $\eta$, at general temperatures $T$, in a BCS-BEC crossover scheme which is demonstrably consistent with conservation laws. The study of $\eta$ is important because it constrains microscopic theories by…

Quantum Gases · Physics 2011-08-04 H. Guo , D. Wulin , C. C. Chien , K. Levin

We study the temperature dependence of the ratio of the shear viscosity to entropy density for the LQCD-contrasted hadron resonance gas of different finite system-sizes, which may represent the final state hadronic matter, formed in systems…

High Energy Physics - Phenomenology · Physics 2018-12-05 Nachiketa Sarkar , Premomoy Ghosh

We present the first ab initio determination of the shear viscosity eta of the Unitary Fermi Gas, based on finite temperature quantum Monte Carlo calculations and the Kubo linear-response formalism. We determine the temperature dependence…

Quantum Gases · Physics 2012-07-16 Gabriel Wlazłowski , Piotr Magierski , Joaquín E. Drut

The temperature and density dependence of the relaxation times, thermal conductivity, shear viscosity and bulk viscosity for a hot and dense gas consisting of pions, kaons and nucleons have been evaluated in the kinetic theory approach. The…

We investigate the temperature dependence of the shear viscosity to entropy density ratio $\eta/s$ using a piecewise linear parametrization. To determine the optimal values of the parameters and the associated uncertainties, we perform a…

We calculate thermodynamic quantities and transport coefficients of a hadronic gas using a Monte Carlo hadronic collision event generator URASiMA. The obtained shear viscosity to entropy density ratio of the hadronic gas is approximately…

Nuclear Theory · Physics 2009-11-10 Shin Muroya , Nobuo Sasaki

We investigate the low-temperature behavior of the ratio between the shear viscosity \eta and the entropy density s in the unitary Fermi gas by using a model based on the zero-temperature spectra of both bosonic collective modes and…

Quantum Gases · Physics 2011-11-08 Luca Salasnich , Flavio Toigo

The shear and the bulk viscosities of the hadron gas at low temperatures are studied in the model with constant elastic cross sections being relativistic generalization of the hard spheres model. One effective radius ${r=0.4 fm}$ is chosen…

High Energy Physics - Phenomenology · Physics 2015-03-19 Oleg N. Moroz

Time evolution of shear viscosity $\eta$, entropy density $s$, and their ratio $\eta / s$ in the central area of central gold-gold collisions at NICA energy range is studied within the UrQMD transport model. The extracted values of energy…

Nuclear Theory · Physics 2020-01-15 M. Teslyk , L. Bravina , O. Panova , O. Vitiuk , E. Zabrodin

The shear viscosity of an interacting pion gas is studied using the Kubo formalism as a microscopic description of thermal systems close to global equilibrium. We implement the skeleton expansion in order to approximate the retarded…

High Energy Physics - Phenomenology · Physics 2012-09-05 Robert Lang , Norbert Kaiser , Wolfram Weise

The shear ($\eta$) and bulk ($\zeta$) viscosities are calculated in a quasiparticle relaxation time approximation. The hadron phase is described within the relativistic mean field based model with scaled hadron masses and couplings. The…

Nuclear Theory · Physics 2010-10-19 A. S. Khvorostukhin , V. D. Toneev , D. N. Voskresensky

We investigate the collision energy dependence of shear viscosity over the entropy density ratio $\eta/s$ in Au+Au collisions at $\sqrt{s_{NN}}=19.6, 39$, and $62.4$ GeV, using Bayesian statistical analysis and Gaussian process emulators to…

Nuclear Theory · Physics 2016-10-04 Jussi Auvinen , Jonah E. Bernhard , Steffen A. Bass

The shear viscosity $\eta$ for a dilute classical gas of hard-sphere particles is calculated by solving the Boltzmann kinetic equation in terms of the weakly absorbed plane waves. For the rare-collision regime, the viscosity $\eta$ as a…

Statistical Mechanics · Physics 2018-01-29 A. G. Magner , M. I. Gorenstein , U. V. Grygoriev

We have calculated microscopically bulk viscosity of hadronic matter, where equilibrium thermodynamics for all hadrons in medium are described by Hadron Resonance Gas (HRG) model. Considering pions and nucleons as abundant medium…

Nuclear Theory · Physics 2016-12-20 Sabyasachi Ghosh , Sandeep Chatterjee , Bedangdas Mohanty

We propose a method for extracting the shear viscosity over entropy density ratio (eta/s) of the quark-gluon plasma from experimental data. We argue that uncertainty due to poor knowledge of the earliest stages of a heavy-ion collision is…

Nuclear Theory · Physics 2013-05-14 Matthew Luzum , Jean-Yves Ollitrault

The determination of the shear viscosity is a central topic in various areas of modern physics. In particular, it is often necessary to evaluate the shear viscosity $\eta$ of fluids made up of more than one species, all interacting with…

High Energy Physics - Phenomenology · Physics 2025-12-15 Gabriele Parisi , Vincenzo Nugara , Salvatore Plumari , Vincenzo Greco

Using the (2+1)-dimensional viscous hydrodynamic code VISH2+1 with a temperature dependent specific shear viscosity (eta/s)(T), we present a detailed study of the influence of a large hadronic shear viscosity and its corresponding…

Nuclear Theory · Physics 2015-03-17 Chun Shen , Ulrich W Heinz

Elaborated calculations of the shear and the bulk viscosities in the hadron gas, using the ultrarelativistic quantum molecular dynamics (UrQMD) model cross sections, are made. These cross sections are analyzed and improved. A special…

High Energy Physics - Phenomenology · Physics 2013-09-23 Oleg Moroz